Blood component processing system, apparatus, and method

ABSTRACT

A system and method are used in connection with processing of blood components. The processing of blood components may involve centrifugal separation and/or filtering of the blood components. In some examples, at least some blood components are centrifugally separated in a chamber and then filtered via a filter rotating along with a centrifuge rotor, wherein the filter is located closer than the chamber to an axis of rotation of the rotor. The filter may include a porous filtration medium configured to filter leukocytes, platelets, and/or red blood cells. Some examples include a pressure sensor sensing pressure of pumped blood components. The sensed pressure may be used in connection with controlling the pumping of the blood products and/or in connection with determining the location of an interface associated with the blood products. Other uses of the sensed pressure are also possible.

[0001] This application claims the benefit of priority under 35 U.S.C. §119(e) of the following U.S. provisional patent applications: No.60/373,083, filed Apr. 16, 2002, and No. 60/405,667, filed Aug. 23,2002.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a system, apparatus, and methodfor processing components of blood. In particular, some aspects of theinvention relate to processing blood components through the use ofcentrifugal separation, filtration, and/or any other form of processing.

[0004] 2. Description of the Related Art

[0005] Whole blood consists of various liquid components and particlecomponents. The liquid portion of blood is largely made up of plasma,and the particle components include red blood cells (erythrocytes),white blood cells (leukocytes), and platelets (thrombocytes). Whilethese constituents have similar densities, their average densityrelationship, in order of decreasing density, is as follows: red bloodcells, white blood cells, platelets, and plasma. In terms of size, theparticle constituents are related, in order of decreasing size, asfollows: white blood cells, red blood cells, and platelets. Most currentseparation devices rely on density and size differences or surfacechemistry characteristics to separate blood components.

[0006] Separation of certain blood components is often required forcertain therapeutic treatments involving infusion of particular bloodcomponents into a patient. For example, in a number of treatmentsinvolving infusion of platelets, there is sometimes a desire to separateout at least some leukocytes and/or red blood cells before infusing aplatelet-rich blood component collection into a patient.

[0007] For these and other reasons, there is a need to adopt approachesto processing components of blood.

SUMMARY

[0008] In the following description, certain aspects and embodiments ofthe present invention will become evident. It should be understood thatthe invention, in its broadest sense, could be practiced without havingone or more features of these aspects and embodiments. It should also beunderstood that these aspects and embodiments are merely exemplary.

[0009] One aspect of the invention relates to a system for processingblood components. The system may comprise a separation chamber includinga chamber interior in which blood components are centrifugally separatedand an outlet port for passing at least some centrifugally separatedblood components from the chamber interior. A flow path may be in flowcommunication with the outlet port of the separation chamber. Theapparatus may further comprise a filter including a filter inlet in flowcommunication with the flow path, a porous filtration medium configuredto filter at least some of at least one blood component (e.g.,leukocytes, platelets, and/or red blood cells) from centrifugallyseparated blood components passed to the filter via the flow path, and afilter outlet for filtered blood components. The system may furthercomprise a rotor configured to be rotated about an axis of rotation. Therotor may comprise a first portion configured to receive the separationchamber and a second portion configured to receive the filter, whereinthe first and second portions may be positioned with respect to oneanother so that when the separation chamber is received in the firstportion and the filter is received in the second portion, the filter iscloser than the interior of the separation chamber to the axis ofrotation. The system may be configured so that the rotor rotates duringfiltering of at least one blood component via the filter.

[0010] In another aspect, the system may be configured so that when thefilter is received in the second portion, the filter is eccentric withrespect to the axis of rotation. For example, the system may beconfigured so that the filter is at least close to the axis of rotation(i.e., close to the axis of rotation or intersecting the axis ofrotation at least partially) and so that the axis of rotation does notintersect an interior flow path defined by the filter. In some examples,when the filter is received in the second portion, the filter may beoffset from the axis of rotation so that the axis of rotation does notintersect the filter. In some examples, the filter is eccentricallypositioned so that blood components exit a housing of the filter (and/orenter the filter itself) at a location that is at least close to therotor's axis of rotation, as compared to the location where the bloodcomponents enter the filter housing (and/or where the blood componentsexit the filter itself).

[0011] In a further aspect, the system may be configured so that whenthe filter is received in the second portion, a filter housing outflowport is located closer than a filter housing inflow port and/or theporous filtration medium to the axis of rotation. In another aspect, thefilter housing outflow port may be above the filter housing inflow port.

[0012] In an additional aspect, the filter may comprise a filter housingdefining an interior space containing the porous filtration medium,wherein the filter inlet and filter outlet may be in flow communicationwith the interior space, and wherein the system may be configured sothat when the filter is received in the second portion, the filter ispositioned so that blood components flow in the interior space in adirection facing generally toward the axis of rotation. In someexamples, the filter housing defines a filter housing inflow port forpassing blood components to the interior space and a filter housingoutflow port for passing blood components from the interior space. Thesystem may be configured so that when the filter is received in thesecond portion, the filter housing outflow port is closer than thefilter housing inflow port (and/or the porous filtration medium) to theaxis of rotation. In an exemplary arrangement, the filter housingoutflow port is above the filter housing inflow port.

[0013] In a further aspect, the second portion may comprise at least oneof a ledge and a slot configured to receive the filter, the at least oneof a ledge and a slot being positioned under a top surface of the rotor.Alternatively (or additionally), the rotor may comprise a holderconfigured to hold the filter with respect to the rotor.

[0014] There are many possible arrangements for the flow path. In someexamples, the flow path may include tubing. For example, the flow pathmay include a first tubing portion having one end coupled to the outletport of the separation chamber and another end coupled to the filterinlet. In addition, the apparatus may also include a second tubingportion having an end coupled to the filter outlet, wherein the secondtubing portion extends in a direction facing generally away from theaxis of rotation. Further, the system may include a third tubing portiondownstream from the second tubing portion, wherein the third tubingportion extends in a direction facing generally toward the axis ofrotation.

[0015] In one more aspect, the rotor may comprise a groove configured toreceive at least some of the tubing (e.g., at least some of the secondand third tubing portions).

[0016] One other aspect relates to an apparatus for use with acentrifuge for processing blood components. The apparatus could beconfigured in a number of different ways. According to one aspect, theapparatus may comprise the separation chamber, the flow path, and thefilter. In some embodiments, the apparatus is configured to be disposedafter being used for processing of blood components.

[0017] In some embodiments, the rotor's axis of rotation may extendthrough the second portion of the rotor.

[0018] In another aspect, the system may comprise at least one valvingmember on the centrifuge rotor, the valving member being configured tocontrol flow of at least some of the blood components during rotation ofthe rotor. In some examples, the valving member may comprise a tubingclamp.

[0019] In a further aspect, the system may comprise at least one sealingmember on the centrifuge rotor, the sealing member being configured tocreate a seal during rotation of the rotor. For example, the sealingmember may comprise a tubing welder.

[0020] In one further aspect, the rotor may comprise at least onesupport member configured to support the chamber, wherein the at leastone support member may comprise a guide groove configured to receive aportion of the tubing line and a controllable clamp and/or welderassociated with the groove. For example, the clamp may be configured tocontrollably occlude flow of blood components through the tubing line.In some examples, the chamber may comprise at least one guide holeconfigured to receive the at least one support member.

[0021] In some embodiments, the rotor may comprise a plurality ofsupport members located in an asymmetric fashion with respect to theaxis of rotation, and the chamber may comprise a plurality of guideholes, each of the guide holes being configured to receive a respectiveone of the support members.

[0022] According to another aspect, the system may further comprise apump configured to pump at least some blood components from the chamber.The system may also comprise a pressure sensor configured to sensepressure of the pumped blood components, wherein the system may beconfigured to control the pump based on at least the pressure sensed bythe pressure sensor.

[0023] A further aspect relates to a system comprising a chamber (e.g.,a blood separation chamber) that may comprise an interior configured tocontain separated blood components, and an outlet port for passing atleast some of the separated blood components from the interior. A flowpath may be in flow communication with the outlet port of the chamber.The system may further comprise a filter comprising a filter inlet inflow communication with the flow path, a porous filtration mediumconfigured to filter at least some of at least one blood component fromseparated blood components passed to the filter via the flow path, and afilter outlet for filtered blood components. In addition, the system mayalso comprise a pump configured to pump at least some of the separatedblood components from the chamber to the filter via the flow path, and apressure sensor configured to sense pressure of blood components pumpedto the filter. The system may be configured to control the pump based onat least the pressure sensed by the pressure sensor.

[0024] In some embodiments, the pump may comprise a portion of acentrifuge and/or at least a portion of a blood component expressor.

[0025] According to another aspect, the system may be configured suchthat the system calculates a difference between pressures sensed by thepressure sensor in at least one time interval, determines when thecalculated difference is at least a predetermined amount, and controlsthe pump in response to at least the determination that the calculateddifference is at least the predetermined amount.

[0026] In yet another aspect, there is a system that may comprises aseparation chamber comprising a chamber interior in which bloodcomponents are centrifugally separated, and an outlet port for passingat least some of the centrifugally separated blood components from thechamber interior. A flow path may be in flow communication with theoutlet port of the separation chamber. The system also may comprise apump configured to pump at least some of the centrifugally separatedblood components from the chamber and through the flow path, and apressure sensor configured to sense pressure of blood components pumpedby the pump. In addition, the system may comprise a centrifuge rotorconfigured to be rotated about an axis of rotation, the rotor comprisinga portion configured to receive the separation chamber. The system maybe configured such that the system calculates a difference betweenpressures sensed by the pressure sensor in at least one time interval,determines when the calculated difference is at least a predeterminedamount, and controls the pump in response to at least the determinationthat the calculated difference is at least the predetermined amount.

[0027] Many different types of chambers are possible. In someembodiments, the chamber may have a ring shape.

[0028] According to another aspect, the chamber may comprise a bag(e.g., a blood component separation bag). For example, at least aportion of the bag may be formed of at least one of flexible andsemi-rigid material so that the chamber interior has a variable volume.In some embodiments, the bag may have a generally annular ring shapedefining a central opening.

[0029] In another aspect, the chamber interior may include a taperedportion leading to the outlet port.

[0030] In a further aspect, the chamber may be configured so that thechamber has a variable volume, and the pump may be configured to reducethe volume of the chamber interior. In one example, the pump may beconfigured to apply pressure to the chamber via hydraulic fluid. Such anexample may also include a sensor configured to sense pressure of pumpedblood products, wherein the sensor may be configured to sense pressureof the hydraulic fluid. Certain aspects of the invention could bepracticed with or without a pump and/or pressure sensor, and when suchstructure is present, there are many possible forms of pumping andsensing configurations that could be used.

[0031] In an even further aspect, the system may further comprise anoptical sensor, and the system may be configured to control the pumpbased on at least one of information sensed by the optical sensor andpressure sensed by the pressure sensor. In one example, an opticalsensor may be positioned to sense blood components in the chamber,and/or an optical sensor may be positioned to sense blood components atanother location, such as a location associated with the flow path(e.g., at a tubing line in flow communication with the filter).

[0032] In another aspect, the system may be configured so that the pumppumps blood components from the chamber during rotation of thecentrifuge rotor.

[0033] In a further aspect, the apparatus may further comprise acollection container comprising an inlet in flow communication with thefilter outlet and/or the flow path, and/or a portion of the rotor mayfurther comprise a cavity configured to receive the collection containerand possibly also the filter. In some examples, there may be more thanone collection container and/or at least one collection container may belocated outside of a centrifugal field during blood componentprocessing.

[0034] One more aspect of the invention relates to a method ofprocessing blood components.

[0035] Some exemplary methods may include providing a system disclosedherein. The term “providing” is used in a broad sense, and refers to,but is not limited to, making available for use, manufacturing, enablingusage, giving, supplying, obtaining, getting a hold of, acquiring,purchasing, selling, distributing, possessing, making ready for use,forming and/or obtaining intermediate product(s), and/or placing in aposition ready for use.

[0036] In one more aspect, a method may comprise placing a separationchamber in a first portion of a centrifuge rotor and a filter in asecond portion of the rotor, wherein the filter is located closer thanan interior of the separation chamber to the axis of rotation of therotor, and wherein the filter comprises a porous filtration medium. Themethod may further comprise rotating the centrifuge rotor, theseparation chamber, and the filter about the axis of rotation of thecentrifuge rotor, wherein the blood components are centrifugallyseparated in the chamber interior. In addition, the method may compriseremoving at least some of the centrifugally separated blood componentsfrom the separation chamber, and filtering the removed blood componentswith the filter so as to filter at least some of at least one bloodcomponent (e.g., leukocytes, platelets, and/or red blood cells) from theremoved blood-components, wherein at least a portion of the filteringoccurs during said rotating.

[0037] In another aspect, the method may further comprise pumping atleast some of the centrifugally separated blood components from thechamber to the filter. A further aspect may include sensing pressure ofpumped blood components, and controlling the pumping based on at leastthe sensed pressure.

[0038] In yet another aspect, there is a method comprising pumping atleast some separated blood components from a chamber (e.g., a bloodseparation chamber or any other type of chamber structure), filteringthe pumped blood components with a filter so as to filter at least someof at least one blood component from the pumped blood components,sensing pressure of blood components pumped to the filter, andcontrolling the pumping based on at least the pressure sensed by thepressure sensor. In some examples, the chamber may be rotated (e.g., viaa centrifuge) and separated blood components may be pumped from thechamber while the chamber is received on a centrifuge rotor and/or afterthe chamber is removed from a centrifuge rotor.

[0039] A further aspect relates to a method of determining a location ofat least one interface during processing of blood components, whereinthe method comprises pumping at least some centrifugally separated bloodcomponents from a chamber, sensing pressure of the pumped bloodcomponents, and determining a location of at least one interface basedon the sensed pressure, wherein the interface is associated with thepumped blood components. For example, the interface may be an interfacebetween blood components and air, and/or an interface between differingblood components.

[0040] In another aspect, the method may comprise calculating adifference between pressures sensed in at least one time interval,determining when the calculated difference is at least a predeterminedamount, and controlling the pumping in response to at least thedetermination that the calculated difference is at least thepredetermined amount.

[0041] According to another aspect, there is a method of processingblood components, comprising rotating a chamber about an axis ofrotation, wherein blood components are centrifugally separated in thechamber, pumping at least some separated blood components from thechamber, sensing pressure of pumped blood components, calculating adifference between pressures sensed in at least one time interval,determining when the calculated difference is at least a predeterminedamount, and controlling the pumping in response to at least thedetermination that the calculated difference is at least thepredetermined amount.

[0042] In another aspect, the method may further comprise passing bloodcomponents (e.g., filtered blood components) into at least onecollection bag.

[0043] In a further aspect, the blood components in the chamber may beblood components of a buffy coat. Buffy coat blood components aregenerally blood components that result from a procedure where plateletsand leukocytes along with some amount of red blood cells and plasma havebeen separated from whole blood. Alternatively, any other substancecontaining one or more blood components could be processed.

[0044] In some examples, whole blood may be processed in the method. Forexample, whole blood may be introduced into the chamber (e.g., fromone/or more donors, and/or from one or more containers containing blooddonated by one or more donors). In the processing of whole blood, anynumber of blood components may be centrifugally separated, filtered,and/or processed in any other way. For example, components of wholeblood may be separated and pumped into separate, respective containers(optionally while being filtered via one or more filters).

[0045] In one more aspect, when blood components are pumped, the pumpingmay comprise reducing the volume of an interior of the chamber. Forexample, the method may comprise applying pressure to the chamber viahydraulic fluid.

[0046] In another aspect, the pumping may occur during rotation of acentrifuge rotor.

[0047] In yet another aspect, the method may comprise optically sensingpumped blood products, and controlling the pumping based on at least oneof optically sensed information and sensed pressure. For example, theoptically sensing may comprise optically sensing blood components in thechamber and/or optically sensing blood components in a tubing line(e.g., a tubing line in flow communication with a filter).

[0048] In another aspect, the method may further comprise causing atleast one valving member on the centrifuge rotor to control flow of atleast some of the blood components during rotation of the rotor. Asmentioned above, the valving member may comprise a tubing clamp.

[0049] In a further aspect, the method may further comprise causing atleast one sealing member on the centrifuge rotor to create a seal duringrotation of the rotor. As mentioned above, the sealing member maycomprise a tubing welder.

[0050] Aside from the structural and procedural arrangements set forthabove, the invention could include a number of other arrangements suchas those explained hereinafter. It is to be understood that both theforegoing description and the following description are exemplary only.

BRIEF DESCRIPTION OF THE DRAWINGS

[0051] The accompanying drawings are incorporated in and constitute apart of this specification. The drawings illustrate exemplaryembodiments and, together with the description, serve to explain someprinciples of the invention. In the drawings,

[0052]FIG. 1 is a schematic cross-section view of an embodiment of asystem in accordance with the present invention;

[0053]FIG. 1A is a view similar to that of FIG. 1 showing an alternateembodiment of the system;

[0054]FIG. 1B is a top plan view of another alternative embodiment ofthe system;

[0055]FIG. 2 is a top plan view of a portion of an apparatus including achamber and filter for use with the systems of FIGS. 1, 1A, and 1B,wherein line I-I of FIG. 2 represents the plane for the cross-sectionviews of the chamber portion shown in FIGS. 1 and 1A;

[0056]FIG. 3 is partially schematic view of an embodiment of anapparatus including the chamber and filter of FIG. 2;

[0057]FIG. 4 is an isometric view of a system including the apparatus ofFIG. 3;

[0058]FIG. 5 is a graph showing pressure plotted over time in connectionwith an example involving the embodiment of FIG. 1B;

[0059]FIG. 6 is a top, partially schematic view of an alternativeembodiment of a separation chamber;

[0060]FIG. 7 is a schematic view of an example of a controllercommunicating with various possible system components;

[0061]FIG. 8 is a schematic, partial cross-section view illustrating theconfiguration of a filter and separation chamber associated with thesystem embodiment of FIG. 1B;

[0062]FIG. 8a is a schematic, partial cross-section view of analternative filter configuration;

[0063]FIG. 8b is a schematic, partial cross-section view of anotheralternative filter configuration;

[0064]FIG. 9 is a schematic view of a hydraulically operated pump andpressure sensor associated with the system embodiments of FIGS. 1, 1A,and 1B;

[0065]FIG. 10 is a schematic view of an alternative embodiment of asystem associated with a centrifuge;

[0066]FIG. 11 is a schematic view of an alternative embodiment of asystem associated with a blood component expresser;

[0067]FIG. 12 is a schematic view of an alternative embodiment of asystem associated with a blood component expressor; and

[0068]FIG. 13 is a schematic view of an embodiment of a systemconfigured to process whole blood.

DESCRIPTION OF A FEW EXEMPLARY EMBODIMENTS

[0069] Reference will now be made in detail to a few exemplaryembodiments of the invention. Wherever possible, the same referencenumbers are used in the drawings and the description to refer to thesame or like parts.

[0070]FIG. 1 shows an embodiment of a system for processing bloodcomponents. The system includes a centrifuge 34 in combination with anapparatus including a filter 31 and a chamber 4 in the form of a bloodcomponent separation bag having a ring shape. The centrifuge 34 has arotor 1 including a first rotor portion defining a ring-shaped area 3receiving the chamber 4 and a second rotor portion defining a centercavity 2 where the filter 31 and possibly also a collection container 33(e.g., a bag used to contain blood components processed by the system)may be located during a blood component processing operation.

[0071] The chamber 4 has an interior 8 in which blood components arecentrifugally separated during rotation of the rotor 34 about an axis ofrotation X. As described in more detail below, at least some of theblood components centrifugally separated in the chamber 4 are passed viaa tubing line 21 to a filter 31 where at least some of at least oneblood component (e.g., leukocytes, platelets, and/or red blood cells) isfiltered before passing the filtered blood component(s) to thecollection container 33.

[0072] As described in more detail below, hydraulic fluid in a space 5located beneath the chamber 4 exposes the chamber 4 to an externalpressure that causes at least some centrifugally separated bloodcomponents to be pumped from the chamber 4. The centrifuge rotor 1 alsohas an inner lid 6 adapted to rotate along with a remainder of the rotor1 and the separation chamber 4. The lid 6 is optionally configured to atleast partially secure the chamber 4, for example, in a clamping fashionalong a line 7 shown in FIG. 2. This may be an effective way to fix theposition of the chamber 4 in the centrifuge rotor 1 and limit thestresses on the inner edge of the bag 1. The centrifuge lid 6 optionallydefines a central opening 53 possibly allowing center cavity 2 to beaccessible externally even when the inner lid 6 is in a closed position.

[0073] The centrifuge rotor 1 may include one or more supports 9, 10, 11shown in FIGS. 1B, 2, and 4 (for example, three to five supports). (Theview of FIG. 1 shows only support 9.) Optionally, the supports extendwholly or partially in the center cavity 2 and thus may define thecavity 2. The above-mentioned clamping of the chamber 4 by the inner lid6 may limit, through its greater contact area, the load on the inneredge of the chamber 4 and assist in preventing it from slipping over orbeing released in some other way from supports 8, 9, and 10 duringcentrifuge rotor rotation. As shown in FIGS. 1B and 2, e.g., therespective supports 9-11 are optionally somewhat asymmetric (e.g., aboutthe rotational axis X), and may thus assist in defining the position ofthe chamber 4 and its associated tubes in the rotor 1 while holding thechamber 4 in position during centrifuging.

[0074] Each of the support members 9-11 may define a respective guidegroove, such as groove 12 shown in FIG. 1, which is defined in support9. The groove may be shaped to receive one or more different tubespassing blood components or other fluids in the system. One or more ofthe supports 9-11 may be configured so that the guide grooves may beselectively reduced (and/or increased) in size to clamp (and/or unclamp)tubing placed in the grooves, and thereby accomplish valving forregulating the flow of fluids in the apparatus. For example, a portionof the support 9 could be configured to move in a clamping/unclamplingfashion in the direction of arrow 13 shown in FIG. 1 so as to functionas a clamp valve for tubing 21 in guide groove 12.

[0075] One or more of the supports 9-11 may be configured to weld and/orcut tubes extending in grooves defined in the supports 9-11. Forexample, electric power to perform welding via supports 9-11 may bepassed to the supports 9-11 via an electrical contact between the rotor34 and a centrifuge stand. Various different components of thecentrifuge may also be supplied with power via contact(s). In theembodiment of FIG. 1, the electric power is conveyed via electrical slipring connectors 14, 15 between the rotor and stand portions of thecentrifuge, wherein connector 14 is a rotating part of the centrifugeand connector 15 is a secured part in the centrifuge stand. As shown inFIG. 1, the centrifuge 34 may include a centrifuge motor 16 coupled tothe rotor 1 so as to rotate the rotor 1 about the axis of rotation X.For example, the motor 16 may be coupled to the centrifuge rotor 1 by adriving belt 47 disposed in operative communication with a motor drivingpulley 48 and a centrifuge driving pulley 49. A centrifuge rotationbearing 50 may cooperate with a rotating guide 51.

[0076] As shown schematically in FIG. 1, both the collection container33 and filter 31 may be received in the center cavity 2. The filter 31may be disposed in the cavity 2 in any number of different fashions. Inone example, shown in FIG. 1, the filter 31 may be arranged in thecavity 2 so that components passing through the filter flow in adirection facing generally toward the axis of rotation X. In theembodiment of FIG. 1A, the filter 31 is oriented to position a filterinlet 31 a above a filter outlet 31 b. Due to centrifugal forcesgenerated during rotation of the rotor 1, substances flowing through thefilter 31 of FIG. 1A may flow in a horizontal direction (as viewed inFIG. 1A) as well as in the vertical direction.

[0077] As shown in FIG. 1A, the filter 31 is optionally disposed in agenerally lateral orientation on a small ledge 32 extending into thecavity 2. A covering member such as inner lid 6 may be configured tocontact and/or otherwise cover and hold filter 31 in place. For example,a projection 66 extending from the lid 6 and the ledge 32 may define aholder for the filter 31. Alternatively, the ledge 32 could be movedupwardly from the position shown in FIG. 1A and/or an inner part of thelid could extend slightly lower. In another alternative arrangement, thefilter 31 may be positioned in the cavity 2 without being restrained,such as in the embodiment shown in FIG. 1.

[0078]FIG. 1B shows another embodiment including an alternativeplacement of filter 31. The filter 31 of FIG. 1B is positioned in agenerally lateral orientation with the filter 31 being eccentric withrespect to the axis of rotation X. In addition, the filter 31 of theembodiment of FIG. B is offset slightly from the rotational axis X sothat the axis X does not intersect an interior of the filter 31. Thefilter 31 is positioned so that substances flowing through the filter 31flow in a direction 95 generally facing toward the axis of rotation X.

[0079]FIG. 8 schematically shows an example of how the filter 31 of FIG.1B may be configured. (In FIG. 8, the filter 31 and separation 4 are notdrawn to scale.) As shown in that figure, the filter 31 has a filterinlet 31 a and a filter outlet 31 b at the respective ends of L-shapedtubing segments connected to a filter housing 31 d defining an interiorspace containing a porous filtration medium 31 c. The filter outlet 31 bis located above the filter inlet 31 a; and the filter inlet 31 a islocated closer than both the filter outlet 31 b and filtration medium 31c to the axis of rotation X. The filter housing 31 d defines a filterhousing inflow port 31 e and a filter housing outflow port 31 f abovethe inflow port 31 e. The filter housing outflow port 31 f is closerthan the filter housing inflow port 31 e to the axis of rotation X. Thefilter housing outflow port 31 f is also closer than the filtrationmedium 31 c to the axis of rotation X.

[0080] In some examples, such as that of FIG. 8, the relativepositioning of the filter inlet 31 a, filter outlet 31 b, housing inflowport 31 e, housing outflow port 31 f, and/or medium 31 c, as well as theeccentric (and possibly also offset) positioning of the filter 31, mayassist in clearing most (if not all) air from the interior of thefilter, as compared to alternative filtering arrangements which mightpotentially cause air to be “locked” therein.

[0081]FIG. 8a shows another example of a filter 31 that could be used inthe system. As shown in that figure, filter outlet 31 b is located abovefilter inlet 31 a; and filter inlet 31 a is closer than both filteroutlet 31 b and filtration medium 31 c to the axis of rotation X. Inthis example, rather than having the L-shaped tubing segments shown inFIG. 8, filter housing 31 d defines flow passages leading to and fromfilter outlet 31 b and filter inlet 31 a, respectively, such that filterhousing outflow port 31 f is located closer than both filter housinginflow port 31 e and medium 31 c to the axis of rotation x. In addition,outflow port 31 f is above inflow port 31 e.

[0082]FIG. 8b shows a further example of a filter 31 that could be usedin the system. For this example, housing inflow port 31 e and housingoutflow port 31 f are at substantially the same relative positions asfilter inlet 31 a and filter outlet 31 b, respectively. In contrast tothe filter shown in FIG. 8a, filter housing outflow port 31 f is closerthan both filter housing inflow port 31 e and filtration medium 31 c tothe axis of rotation X. In addition, the inlet 31 a, inflow port 31 e,outflow port 31 f, and outlet 31 b are at substantially the same level.Further, filter outlet 31 b is closer than both filter inlet 31 a andfiltration medium 31 c to the axis of rotation X.

[0083] One feature in common with the filter examples of FIGS. 8, 8a,and 8 b is that blood components flowing in an interior space containingfiltration medium 31 c flow in a direction 95 facing generally towardthe axis of rotation X.

[0084] As partially shown in FIG. 1B, the filter 31 may be positioned atleast partially in a slot 57 offset from the axis of rotation X. Theslot 57 may be wholly or partially defined in lid 6. Alternatively, theslot 57 could be defined using a shelf and projection similar to thoseshown in FIG. 1A.

[0085] Although the embodiments of FIGS. 1, 1A, and 1B show the filterpositioned beneath the top surface of the rotor 34, the filter 31 couldalternatively be arranged partially or completely above the rotor's topsurface. In some alternate embodiments, the filter may even bepositioned at a location that is not within the centrifugal fieldgenerated by rotation of the rotor 1.

[0086] In the embodiments of FIGS. 1, 1A, and 1B, the portion of thecentrifuge rotor defining the ring-shaped area 3 and the portion of thecentrifuge rotor defining the center cavity 2 are positioned withrespect to one another so that when the chamber 4 is received in thearea 3 and the filter 31 is received in the cavity 2, the filter 31 iscloser than the chamber interior 8 to the axis of rotation X, asschematically illustrated in FIG. 8. Such a positioning may avoid thefilter 31 from being subjected to relatively high centrifugal forceswhile permitting substances being centrifugally separated in the chamberinterior 8 to be subjected to such high forces. In some instances, itmay be desired for such a reduced amount of centrifugal force to beapplied to the filter 31. For example, in certain filter arrangements,exposure to relatively high centrifugal forces might cause certainpotential problems associated with bursting of the filter housing, orperhaps negatively affect the filtration efficacy. For some filters,such as those that might not be significantly impacted by centrifugalforces, alternative positioning of the filter might be possible.

[0087] The filtration medium 31 c shown in FIGS. 1A, 8, 8 a, and 8 b maybe any form of porous medium, such as fibers combined together in awoven or unwoven form, loose fibers, foam, and/or one or more membranes,for example. The filtration medium 31 c may be configured to filterleukocytes, platelets, and/or red blood cells.

[0088] The filter 31 could be configured in any known form. In someembodiments, the filter 31 may be a leukoreduction filter configured tofilter leukocytes from blood components including a concentration ofplatelets. One example of such a filter is the LRP6 leukoreductionfilter marketed by the Pall Corporation of Glen Cove, N.Y. Anotherexample is the Sepacell PLS-10A leukocyte reduction filter marketed byBaxter Healthcare Corp. of Deerfield, Ill. A further example is theIMUGARD filter marketed by Terumo of Japan. It should be understood thatother known leukoreduction filters could also be used and such filtersoptionally may be selected depending upon the process being undertaken.

[0089] As shown in FIG. 1B, the inner lid 6 includes one or more grooves60 defined therein for receiving one or more tubing lines. A firsttubing portion 21 a places the blood component separation chamber (notshown in FIG. 1B) and filter 31 in flow communication with one another.Tubing 21 is flow coupled to the outlet of filter 31. The tubing 21includes a second tubing potion 21 b coupled to an outlet of the filter31 and extending in a direction facing generally away from the rotationaxis X. The tubing 21 also includes a third downstream portion 21 cextending in a direction generally facing the axis of rotation X. Thegroove(s) 60 may be configured to receive at least some of the secondand third tubing portions 21 b and 21 c.

[0090] In some embodiments, there may be lids (not shown) other than thelid 6 to account for a plurality of processes which may alternatively beperformed by the system. As shown in FIG. 1B, the groove(s) 60 may bearranged to associate the tubing 21 with one or more other features ofthe embodiment. For example, the groove(s) 60 may be arranged to placethe tubing 21 in cooperation/communication with the groove 12 of member9 (and/or with an optical sensor 55 described below), among otherthings.

[0091] As shown in FIG. 2, the chamber 4 is optionally in the form of abag defined by two sheets of a suitable plastic material (e.g., flexibleand/or semi-rigid plastic material) joined together by circumferentiallywelding radially inner and outer edges 17 and 18. Between the weldededges 17 and 18, there is an open, ring-shaped chamber interior in whichblood components are separated. The chamber 4 includes a central opening(e.g., aperture) 19 which primarily corresponds to the center cavity 2opening. Such a structure may simplify access to the center cavity 2.The chamber 4 shown in FIG. 2 has respective guide holes 109, 110, and111 for receiving supports 9-11, respectively, and thus positioning thechamber 4 with respect to the supports 9-11. The bag materialsurrounding the guide holes 109, 110, and 111 may be welded tostrengthen the material around the holes. The guide holes 109, 110, and111 optionally have an asymmetric arrangement (about rotational axis X)that is like that of the optional asymmetric orientation of the supports9, 10, and 11 so as to facilitate orienting the chamber 4.

[0092] At least a portion of the chamber 4 may be formed of flexibleand/or semi-rigid material so that the interior of the chamber 4 has avariable inner volume. For example, the chamber 4 may be formed ofmaterial permitting external pressure to be applied to the chamber so asto reduce the inner volume of the chamber 4. In some exemplaryarrangements, the chamber 4 and possibly the other parts of theapparatus 100 may be formed of material comprising inert plastic.

[0093] The chamber 4 includes an inlet port 4 a for passing bloodcomponents to the interior of the chamber 4 and an outlet port 4 b forpassing at least some centrifugally separated blood components from thechamber interior. Inflow tubing 20 and outflow tubing 21 are placed inflow communication with the ports 4 a and 4 b, respectively, on oppositefacing sides of the chamber 4 via welded sleeve couplings 24. Eachsleeve coupling 24 may be a securing part in the form of a short pieceof tubing with a diagonally arranged flat securing collar which may bewelded to the chamber 4, while permitting the respective tubing 20 and21 to be welded to the coupling 24. Instead of being secured via such asleeve coupling, the tubing could alternatively be secured to (and/orin) each respective welded edge, i.e. within welded edges 17 and 18.

[0094] An alternative embodiment of a chamber 4 is shown in FIG. 6,wherein, a sort of bay 75 is positioned at the outlet port leading totube 21. This bay 75 is defined by a gradually tapered portion formed byweld portions 61 and 62 extending in a generally radial direction fromthe outlet port. (The chamber 4 shown in FIG. 2 may have a similar bay.)This type of arrangement may enable platelets to be received in arelatively non-abrupt or otherwise non-disruptive process. This mayenhance the quality of the harvested platelets.

[0095] Referring again to FIG. 6, an inlet area 65 in the region of aninlet port leading from tube 20 does not have a tapered portion definedby weld portions 63, 64. This configuration may alleviate any potentialcapture of platelets (or some other desired product) so as to permitplatelets to be available for harvesting at the outlet area 75.

[0096] When the chamber 4 is formed in a ring shape, as shown in thedrawings, the chamber 4 and at least certain aspects of the centrifuge34 may be configured like the separation chambers and associatedcentrifuges disclosed in one or more of the following patent documents:WO 87/06857, U.S. Pat. No. 5,114,396, U.S. Pat. No. 5,723,050, WO97/30715, and WO 98/35757, for example. Many alternative arrangementsare also possible.

[0097] Although the embodiments shown in the drawings include aseparation chamber in the form of a ring-shaped bag, it should beunderstood that there are many alternative forms of separation chamberconfigurations that could be used. For example, the separation chambercould be in the form of a bag other than a ring-shaped bag.Alternatively, the separation chamber could be in other non-bag forms,such as, for example, in the form of one of the separation vesselsdisclosed in U.S. Pat. No. 6,334,842.

[0098] In one alternative embodiment (not shown), a filter similar to(or identical to) filter 31 could be positioned in tubing 20 to filterat least some blood components (e.g., leukocytes, platelets, and/or redblood cells) from substances being passing into the chamber 4.

[0099]FIG. 3 shows an embodiment of an apparatus 100 including thechamber 4 and filter 31 shown in FIG. 2. This exemplary apparatus 100 isin the form of a bag set for producing platelets from a buffy coatcollection. The apparatus 100 further includes a bag 23 containingdiluting solution, a solution tube 30, four connecting tubes 25-28intended to be coupled (e.g., via welding) to respective bags containingpreviously prepared buffy coat products (not shown), and a multi-wayconnector 29 connecting the tubes 25-28 and 30 to the inflow tubing 20coupled to the inlet port of chamber 4. From the chamber 4, the tubing21 having filter 31 in-line is coupled to an inlet 33 a of collectioncontainer 33, which is in the form of a bag. In an area where thesolution tube 30 is coupled to the solution bag 23, there may be ablocking switch 45 (e.g., frangible member) capable of being placed inan open, flow-permitting position by bending the tube 30 and breakingopen the connection so as to initiate the addition of diluting solutionto bags (not shown in FIG. 3) connected to tubing lines 25-28. Beforethe blocking switch 45 is opened, solution tube 30 may be arranged in aguide groove 12 defined by one of the supports 9-11 so as to provide aclamp valve intended for controlling the addition of diluting fluid tobuffy coat bags associated with lines 25-28

[0100] Although four connecting tubes 25-28 are shown in FIG. 3, anynumber of tubes may be used. For example, the number of connecting tubesmay be between four and six or between four and eight.

[0101] The system embodiments of FIGS. 1, 1A, and 1B include a pumpconfigured to pump at least some centrifugally separated bloodcomponents from the chamber 4 to the filter 31, and those embodimentsalso include a pressure sensor configured to sense pressure of thepumped blood components. As shown schematically in FIG. 9, a pump 80 mayinclude a hydraulic fluid flow passage 88 passing through centrifugerotor 1. One end of the hydraulic fluid flow passage 88 is in flowcommunication with a portion of ring-shaped area 3 positioned beneaththe chamber 4 and separated from the chamber 4 via a flexible membrane22. Another end of the hydraulic fluid flow passage 88 is in flowcommunication with a hydraulic fluid pressurizer 84 including a pistonmovable in a hydraulic fluid cylinder via a driver motor 82 (e.g., astepper motor that moves a lead screw). Optionally, a hydraulic fluidreservoir 86 and associated hydraulic fluid valve 90 may be used tointroduce and/or remove hydraulic fluid to/from the hydraulic fluid flowpassage 88.

[0102] In response to a control signal from a controller 68, the drivermotor 82 drives the piston of pressurizer 84 so as to pressurize ordepressurize hydraulic fluid in the flow passage 88 (e.g., depending onthe direction of travel of the pressurizer piston). The pressurizationof the hydraulic fluid causes pressure to be applied to the chamber 4via the hydraulic fluid pressing against membrane 22. The pressureapplied to the chamber 4 causes the interior volume of the chamber 4 tobecome reduced and thereby pump centrifugally separated blood componentsfrom the chamber 4. Increasing the pressure of the hydraulic fluidcauses an increase in the flow rate of the blood components pumped fromthe chamber 4. Conversely, a decrease of the hydraulic fluid pressurecauses a decrease (or halting) of the pumped flow of blood componentsfrom the chamber 4.

[0103] The pressure of the hydraulic fluid is related to the pressure ofblood components being pumped from the chamber 4. As shown in FIG. 9, apressure sensor 70 is configured to monitor the pressure of thehydraulic fluid in the hydraulic fluid flow passage 88. Due to therelationship between the pressure of the hydraulic fluid and thepressure of the pumped blood components, the hydraulic fluid pressuresensed by the pressure sensor 70 reflects the pressure of the bloodcomponents pumped from the chamber 4. In other words, the pressuresensed by the pressure sensor 70 of FIG. 9 is essentially the same as(or at least proportional to) the pressure of the pumped bloodcomponents.

[0104] The hydraulic fluid may be any suitable substance. For example,the hydraulic fluid may be a fluid having a density slightly greaterthan that of packed red blood cells. One example of such a substance isGlycol. The hydraulic fluid may alternatively comprise oil.

[0105] A number of different pumping and/or blood component pressuresensing arrangements other than those shown in FIG. 9 are possible. Forexample, the amount of current needed to drive the driver motor 82associated with the hydraulic fluid pressurizer 84 may indicate thepressure of both the hydraulic fluid and the blood components. In otherexamples, the pressure of the blood components could be sensed moredirectly (e.g., not via hydraulic fluid) using any type of pressuresensor.

[0106] The pump 80 may be controlled based at least partially on thepressure sensed by the pressure sensor 70. In the embodiment of FIG. 9,the controller 68 could be configured to control the driver motor 82based at least partially on the pressure sensed by the pressure sensor70. For example, the controller 68 could be configured such that thecontroller 68 calculates a difference between pressures sensed by thepressure sensor 70 in at least one time interval while blood componentsare pumped by the pump 80, determines when the calculated difference isat least a predetermined amount, and controls the pump 80 in response toat least the determination that the calculated difference is at leastthe predetermined amount. Such an arrangement could enable a feedbackcontrol of the pump 80, for example, when the pump is initially operatedvia a volume flow rate command.

[0107] As explained in more detail below, in a procedure attempting tocollect a maximum number of platelets and a minimum number of white andred blood cells, the control of the pump 80 based at least partially onthe sensed pressure may be used to stop the pumping of the bloodcomponents from the chamber 4 in response to an increased pressurereflecting that relatively viscous red blood cells are entering thefilter 31 and causing an occlusion of flow through the filter 31.

[0108] The pressure sensed by the pressure sensor 70 could enable adetermination of the location of one or more interfaces associated withseparated blood components being pumped from the chamber 4. For example,the pressure sensed by the pressure sensor 70 could indicate thelocation of an interface between blood components and air present in thesystem at the start-up of a blood component processing procedure. Insuch an example, an increase in pressure might reflect that an air-bloodcomponent interface is near (or at) a radially outward portion of afluid flow path (e.g., in FIG. 1B, the location F₀). In another example,the pressure could provide an indication of the location of an interfacebetween blood components having differing viscosities. For example, anincrease of the pressure sensed by the pressure sensor 80 during thefiltering of at least some blood components via the filter 31 couldprovide an indication that a blood component interface (e.g., between afirst phase including primarily liquid (i.e., plasma and possibly one ormore liquid additives) and platelets, and a second phase includingprimarily red blood cells and white blood cells) is located near (or at)the filter 31, and/or a particular location in the flow path leading toor from the filter 31, and/or a particular location in the chamber 4.

[0109] The pressure sensed by the pressure sensor 70 could reflect a“fingerprint” of the operation of the system. For example, the sensedpressure could reflect one or more of the following: a kinking of fluidflow lines; a leak (e.g., rupture) of the membrane 22, chamber 4, and/orflow path leading to and from the filter; an increased likelihood ofplatelet activation (e.g., a high pressure might reflect forcing ofplatelets through the filter 31); a defect and/or clogging associatedwith the filter 31; and/or a possible need for maintenance (e.g., anindication that the membrane 22 is worn).

[0110] The pressure sensed by the pressure sensor 70 could also be usedto optimize (e.g., reduce) the time for processing (e.g., separation) ofblood components. For example, when the pressure sensed by the pressuresensor 70 indicates a location of particular blood components, the pump80 could be controlled to use differing flow rates for differing bloodcomponents (e.g., use a faster flow rate for pumping certain bloodcomponents, such as plasma).

[0111] In addition to pressure sensor 70, embodiments of the system mayalso include one or more optical sensors for optically sensing bloodcomponents, and the pumping of the blood components may also becontrolled based on at least information sensed by the opticalsensor(s). As shown schematically in FIGS. 1 and 1A, a first opticalsensor 52 is positioned in the centrifuge rotor 1 adjacent the chamber 4to optically sense blood components in the chamber 4. (Although notshown in FIG. 1B, the embodiment of FIG. 1B also includes such asensor.) In addition, as shown in FIG. 1B, the system also may include asecond optical sensor 55 positioned to optically sense blood componentsflowing through the tubing line 21 at the second tubing portion 21 b,located downstream from the filter 31.

[0112] The optical sensors could be configured in the form of any typeof optical sensor used in association with blood components. One exampleof an optical sensor may include a photocell. The first and secondoptical sensors 52 and 55 may be configured to detect a change of colorof blood components. Such a change of color may be indicative of thelocation of an interface between differing blood component phases, suchas an interface where one of the phases that defines the interfaceincludes red blood cells.

[0113] The first optical sensor 52 may be located at a particular radialposition on the centrifuge rotor 1 so as to sense when an interface hasmoved to that location in the chamber 4. For example, the pumping ofblood components from the chamber 4 could be slowed 9 (e.g., via areduction of hydraulic pressure with the arrangement of FIG. 9) inresponse to the first optical sensor 52 detecting an interface (e.g., aninterface partially defined by red blood cells) approaching a radiallyinward location. Similarly, the second optical sensor 55 may detect thepresence of an interface (e.g., an interface partially defined by redblood cells) along the flow path leading from the chamber 4. In someexamples, the controller 68 could be configured so as to halt pumping ofblood components from the chamber 4 in response to the second sensor 55sensing an interface (e.g., an interface partially defined by red bloodcells) and/or in response to a determination that the difference betweenpressures sensed by the pressure sensor 70 is at least a predeterminedamount.

[0114]FIG. 7 shows a schematic view of an example of the controller 68that may be used to at least partially control certain features of thesystem. The controller 68 communicates with various system components.For example, the controller 68 could communicate with the pump 80,centrifuge motor 16, pressure sensor 70, first optical sensor 52, secondoptical sensor 55, valving structure 72 (e.g., the valves defined bysupports 9, 10, 11), and a control panel 36. The controller 68 may beconfigured to cause rotation of the centrifuge rotor 1 during filteringof at least some blood components (e.g., leukocytes, platelets, and/orred blood cells) via the filter 31 received in the cavity 2. In someembodiments, this may enable centrifugal separation in the chamber 4 andfiltering via the filter 31 to occur at least partially simultaneouslyin a somewhat on-line fashion, as compared to some other approacheswhere filtering takes place a period of time after initial centrifugalseparation and removal of a separation chamber and possibly also afilter from a centrifuge rotor. Alternatively (or additionally), thecontroller 68 may be configured so that filtering via the filter 31takes place at least some time after at least an initial separation ofblood components in the chamber 4.

[0115] The controller 68 may control the rotational speed of the rotor1. In addition, the controller 68 may control the pump 80 and/or valvingstructure 72 to control the pumping of substances flowing to and fromthe chamber 4 and the filter 31. The controller 68 may include aprocessor having programmed instructions provided by a ROM and/or RAM,as is commonly known in the art. Although a single controller 68 havingmultiple operations is schematically depicted in the embodiment shown inFIG. 7, the controlling may be accomplished by any number of individualcontrollers, each for performing a single function or a number offunctions.

[0116] The controller 68 may be configured to pump hydraulic fluid at aspecified flow rate. This flow rate may cause a blood component flowrate with a resultant pressure. The controller 68 may then take readingsfrom the pressure sensor 70 and change the flow rate based on thosereading so to control flow rate as a function of pressure measured.

[0117] A number of different pumping and/or blood component pressuresensing arrangements other than those shown in FIG. 9 are possible. Inaddition, there are a number of alternative ways in which the pumping ofblood components from the chamber 4 could be controlled.

[0118]FIG. 10 schematically illustrates an embodiment where bloodcomponents are pumped from chamber 4 via a pump 80 positioned downstreamfrom the filter 31 at a location outside of the centrifugal fieldgenerated by rotation of centrifuge rotor 1. Such a pump 80 could beconfigured in the form of a peristaltic pump or any other type of pumpsuitable for pumping blood components.

[0119] As shown schematically in FIG. 10, the pressure sensor 70 coulddirectly sense the pressure of pumped blood components (rather than viahydraulic fluid) from a location on the centrifuge rotor 1.Alternatively (or additionally) the pressure of the blood componentscould be sensed directly by a pressure sensor 70′ located outside of thecentrifugal field caused by rotation of the rotor 1. Similarly, a filter31′ in place of (or in addition to) filter 31 could be located at alocation outside of the centrifugal field of the rotor 1. Additionally,the collection container 33 may be located outside of the centrifugalfield. In a further modification, the system might be modified so thatthere is no filter.

[0120] In other embodiments, at least some structural features might notbe part of a centrifuge structure. For example, FIG. 11 schematicallyshows an embodiment in the form a blood component expressor including apump 80 configured to pump blood components from a chamber 4. The pump80 of FIG. 11 includes a pair of clamping plates 92 and 94 that applypressure to chamber 4 when a clamp driver 96 moves the clamping plates92 and 94 together. A controller 68 controls the pump 80 based at leastpartially on pressure of pumped blood products sensed directly via thesensor 70. The chamber 4 could be a chamber that has been removed from acentrifuge rotor after blood components in the chamber 4 have beenpreviously stratified in a centrifuging procedure.

[0121]FIG. 12 schematically shows an embodiment similar to that of FIG.11, but substituting a pump 80 like that shown in FIG. 10.

[0122] The following provides a discussion of an exemplary bloodprocessing method that could be practiced using the system embodimentsshown in FIGS. 1, 1A, 1B, 2-4, and 6-9. Although the exemplary method isdiscussed in connection with the structure shown in those figures, itshould be understood that the exemplary method could be practiced usingalternative structure. (In addition, the structure shown in thosefigures could be used in alternative methods.)

[0123]FIG. 4 shows certain components of the apparatus shown in FIG. 3,but some of those components are drawn to a smaller scale or are notvisible in FIG. 4. As shown in FIG. 4, centrifuge 34 is shown standingwith its outer lid 35 completely open and locked in that position. Thecentrifuge inner lid 6 (see FIGS. 1 and 1A) has been omitted to showother parts more clearly. Also, the centrifuge rotor 1 and chamber 4have, to a certain extent, been drawn in a simplified manner. Thecentrifuge control panel 36 is also shown schematically.

[0124]FIG. 4 illustrates four blood bags 37-40 containing buffy coatsuspended in a cassette 41, which is mounted on the inside of thecentrifuge outer lid 35. Buffy coat bags 37-40 have individual outputlines connected by sterile welding to tube connectors 25-28 (see FIG.3). The fluid content of the bags is introduced into the chamber 4 viathe tubes 25-28 and connecting tube 20. After (or before) that, thebuffy coat bags 37-40 may be supplied with washing fluid and/or dilutingsolution from diluting solution bag 23 suspended from a holder 44. Thediluting solution contained in the bag 23 may be plasma or any otherstandard diluting solution. An example of a conventional dilutingsolution is a PAS (platelet additive solution), such as, e.g., T-Sol.Diluting solution bag 23 is suspended sufficiently high above bags 37-40to allow the diluting solution to be added in sufficient amounts tothese bags as soon as blocking switch 45 in tube 30 and a clamp valve insupport 11, through which tube 30 is passed, are opened. Communicationbetween bags 37-40 and chamber 4 proceeds via tube 20 which in turnpasses through a clamp valve in support 10, for example, for controllingfluid communication. After the addition of diluting solution insufficient amounts to bags 3740, a motor (not shown) connected with thecassette 41 may be started and operated to move the cassette 41 back andforth in a curved pendulum movement 42 (or alternatively a complete (orsubstantially complete) rotational movement) until all the concentratesubstance in the buffy coat bags 37-40 is resuspended.

[0125] Various arrangements may cause the agitation movement of thecassette 41. For example, the motor driving the cassette movement may beassociated with a gear box, or there may be a crank function or controlof the motor. It may also be theoretically possible to use a hydraulicmotor, but it might have a slower shaking speed and longer mixing time.

[0126] Then, the built-in clamp valve in the support member 10 may beopened so as to cause flow of substantially all of the substance fromthe bags 37-40 to the chamber 4 via the tubing 20. The tube 20 insupport 10 may then be sealed by sterile welding provided by the support10 so as to block fluid communication through the tube 20, andthereafter (or substantially simultaneously therewith) the support 10may cut the tube 20, so that the empty bags 37-40 and bag 23 with anypossible solution and/or concentrates from the buffy coat dilutingsolution mixture may be disposed. If desired, the flushing out of thebuffy coat bags 37-40 could be carried out in one, two, or severalconsecutive flushing operations. After flushing out the buffy coat bags,cassette 41 and holder 44 may then be removed from the centrifuge lid 35and thereafter the centrifuge lid 35 may then be closed and acentrifuging operation may be carried out.

[0127] Before centrifuging, the chamber 4 is placed in the ring-shapedarea 3 (see FIGS. 1 and 1A) and the collection container 33 (see FIGS.1, 1A and 3) and filter 31 are placed in the center cavity 2 (see FIGS.1, 1A, and 1B). During centrifuging, the centrifuge rotor 1 is rotatedabout the axis of rotation X, thereby causing the blood platelet productto be separated from the other buffy coat components (e.g., red andwhite blood cells) in the chamber 4. Then, after (or in someembodiments, during) that separation, at least some of the plateletproduct may be pumped to the collection container 33 by increasing thepressure of hydraulic fluid passed into the ring-shaped area 3 under themembrane 22 shown in FIG. 9, and thereby applying external pressure tothe chamber 4 that causes a reduction of the volume of an interior ofthe chamber 4. As is understood in the art, such a pressure applied byhydraulic fluid may occur during continued centrifugation (continuedrotor spinning). It otherwise may be applied before rotor rotation hasbegun or even after rotation has halted.

[0128] The pumped blood components are removed from the chamber 4,optionally filtered by the filter 31, and then conveyed to collectioncontainer 33. As shown in FIG. 1B, arrows F show flow through portionsof the filter 31 and the tubing line 21 (which passes through the secondsensor 55 and support member 9) and thence into collection container 33.The flow path of material out of chamber 4 begins through first tubingportion 21 a upstream from filter 31. Flow through tubing portion 21 aemanates first from chamber 4, then travels through or near the axis ofrotation X where the centrifugal forces are the lowest (zero or verynear thereto) of any point in the system. The application of hydraulicpressure (and/or the centrifugal force) continues to then push the flowinto the filter 31. As shown in FIGS. 1B and 8, the blood components mayflow in an interior space of the filter housing 31 d in a direction 95facing generally toward the axis of rotation X. After exiting the filterhousing, the blood components flow in a direction generally facing awayfrom the axis of rotation X, through the second tubing line portion 21b, radially outwardly and through the second optical sensor 55. Then,the flow reaches its radially outermost point of travel, here indicatedas point F₀, relative to the axis of rotation X. Flow then proceedsroughly inward via third tubing portion 21 c, while passing through thesupport member 9, and the valving and/or sealing mechanism therein. Theflow then proceeds to the container 33 disposed in the central cavity 2.

[0129] The filter 31 (e.g., a leukoreduction filter) may be configuredto filter at least some undesired components. For example, where thedesired product is platelets, the filter 31 may filter leukocytes and/orred blood cells. The filtration may occur substantially simultaneouslywith the removal (e.g., pumping) of components from the chamber 4, andalso may be performed at least partially during rotation of thecentrifuge rotor 1.

[0130] The exemplary method further includes optical sensing of bloodcomponents via the first and second optical sensors 52 and 55. In theexemplary method, the flow rate at which blood components are pumpedfrom the chamber 4 may be reduced when the first optical sensor 52senses that an interface (e.g., an interface between desired lightersubstance (e.g., platelets) and a darker non-desired concentrate product(e.g., red blood cells and/or leukocytes)) is approaching a radiallyinward location (e.g., a location at or near the tubing 21). Forexample, such a reduction of the flow rate might be achieved by reducingthe hydraulic pressure applied to the membrane 22 shown in FIG. 9.

[0131] The pumping of blood components from the chamber 4 may beinterrupted or halted when the second optical sensor 55 senses aninterface (e.g., an interface defined at least partially by red bloodcells).

[0132] The exemplary method also includes sensing the pressure of bloodcomponents pumped from the chamber 4. In the embodiment shown in FIG. 9,the pressure of the pumped blood components is sensed via sensing of thepressure of the hydraulic fluid used to pump the blood components fromthe chamber 4.

[0133]FIG. 5 illustrates an exemplary graph showing pressure sensed bythe pressure sensor 70 of FIG. 9 relative to time during the processingof blood components in the exemplary method. Prior to a time T₀, thereis relatively little (or no) sensed pressure because there is someinitial time that may be dedicated to mere centrifugation/rotation ofthe centrifuge rotor 1 to effect the separation of the blood componentsinto stratified layers before much hydraulic pressure is added to pumpthe blood products (in some alternative examples, pressure may be addedsooner (or later) and perhaps even from the beginning of the rotation).At time T₀, the pressure of the hydraulic fluid is increased to beginpumping of blood components from the chamber 4. In some examples, thecontroller 68 could provide a relatively constant volume flow rate ofhydraulic fluid, and, as described below, the hydraulic fluid flow couldbe altered based on sensed pressure feedback.

[0134] The initial pumping of blood components from the chamber 4 pushesan interface defined by the blood components and air initially presentin the system at the beginning of the centrifugation. An increasedamount of hydraulic pressure (and corresponding increase in pressure ofthe pumped blood components) occurs up until there is a peak of pressureP₁ at a time T₁. The pressure peak at time T₁ provides an indicationthat the air-blood component interface (e.g., interface between air andplatelet rich plasma) has reached a particular location in the flow pathdefined by the system. For example, the pressure peak at time T₁ mayrepresent that the air-blood component interface is located in thefilter 31. Alternatively, the pressure peak at time T₁ may represent aform of “siphon” effect associated with pumping the air-blood componentinterface to the radially outermost flow path point F₀ shown in FIG. 1B.After reaching the point F₀, substances may encounter a bit ofresistance due to centrifugal forces (which also contribute to keepingheavier phase materials at further radii from the axis of rotation)encountered when flowing back inwardly toward a lesser radius (whichdescribes all points in the flow other than point F₀). Thus, a sort ofback pressure may be built up.

[0135] After the air-blood component interface has been pumped past thelocation identified by the pressure peak at time T₁, the pressurereaches a reduced pressure level P₂ at time T₂. In a time period from T₂to T₃, the pressure remains substantially constant at level P₂ whileblood components (e.g., plasma, possible additive solution(s), andplatelets) are pumped from the chamber 4, through the filter 31, andinto the collection container 33. In the example represented by thegraph of FIG. 5, the controller 68 has reduced the hydraulic pressurelevel to P₃ at time T₃ in response to the first optical sensor 52sensing an interface defined at least partially by red blood cells inthe chamber 4. The reduction of the hydraulic pressure causes acorresponding reduction of the pressure of the pumped blood componentsas well as a reduction of the flow rate of the pumped blood components(as compared to that in the time interval from T₂ to T₃). The reductionof the flow rate of the pumped blood components may reduce thelikelihood that a substantial number of red and white blood cells willpass into the collection container 33. Additional flow rate reductionsmay also be possible for alternative examples.

[0136] The sensed pressure remains relatively constant at pressure P₃immediately after time T3 and then the sensed pressure increasessomewhat rapidly. The increased pressure represents that an interfacedefined between a phase of relatively low viscosity blood components(e.g., primarily liquid (i.e., plasma and possible liquid additive(s))and platelets) and a phase of relatively high viscosity blood components(e.g., primarily red blood cells and white blood cells) is beginning toenter the filter 31. The relatively high viscosity blood cells (e.g.,red blood cells) are unable to pass through the filter 31 as easily asliquids and other relatively low-viscosity components. As the relativelyviscous blood components continue to enter the filter 31, they become“packed” in the filter 31 and cause an increasing back pressure sensedby the pressure sensor 70.

[0137] The controller 68 receives signals indicative of the pressuresensed by the pressure sensor 70. In the exemplary time interval from T₃to T₄, the controller 70 calculates the difference between maximum andminimum pressures sensed by the pressure sensor 70, and the controller70 determines when that calculated difference exceeds a predeterminedamount. Then, in response to such a determination, the controller 70controls the system so as to cause a significant reduction of hydraulicpressure and corresponding halting or ending of the pumping of bloodcomponents from the chamber 4 (e.g., the piston of pressurizer 84 couldbe retracted and/or valve 90 shown in FIG. 9 could be opened).

[0138] In the example shown in FIG. 5, at time T₄, the pressure reachesa peak at P₄ sufficient to cause a pressure difference ΔP (thedifference between P₄ and P₃) indicating that the location of theinterface defined by the viscous blood components has been pumped to(and possibly slightly beyond) the filter 31. In response to thatpressure difference ΔP being determined by the controller 68, thecontroller 68 discontinues the pumping of blood components from thechamber 4 so that an excessive number of the viscous blood componentswill not be passed to the collection container 33. Accordingly, thepressure after T₄ reflects that hydraulic pressure is no longer appliedto the chamber 4.

[0139] In some alternative examples, the system may be configured sothat in response to a sufficient pressure difference, the pressure ofthe hydraulic flow may be altered (increased or decreased) to continuepumping of blood components at a different flow rate. This could happenmultiple times during a single processing procedure.

[0140] For the example shown in FIG. 5, the pressure difference ΔP maybe about 0.2 bar. Many other differentials could be used depending on anumber of factors.

[0141] The generally flat portions of the pressure diagram (e.g.,between T₂ and T₃ or between T₃ and T₄) indicate that there are nosignificant discrete phases of blood components passing from the chamber4. Those flat portions might be interpreted as an indication of adesired flow rate. Such a flow rate may be determined in advance of ablood processing procedure and used as a form of feedback control sothat when the desired flow rate is reached (as measurable by a discretesensor (not shown)), the pressure may be leveled as shown andmaintained, before encountering a pressure difference indicating apossible condition where it might be desire to cease (or otherwisealter) hydraulic pressure.

[0142] In some instances, the actual level of relatively steady pressuresensing (e.g., e.g., between T₂ and T₃ or between T₃ and T₄) might notbe the same or even nearly the same value from one run to another. Thus,the interpretation of the pressure difference may not be determined byany particular pressure point, but rather may be expressed as and/or bedependent upon a certain minimum change in pressure regardless of thestarting or ending pressure level.

[0143] The sensing of the pressure to determine the location ofinterfaces between phases could be used even in some blood componentprocessing procedures that do not include centrifugation separationand/or filtration. For example, in a procedure that includescentrifugation, but not filtration, the sensing of pressure might beused to determine when an interface reaches a radially outermostposition (similar to the position F₀ shown in FIG. 1B.

[0144] After an identification of the location of a blood componentinterface via the pressure sensing and/or the optical sensing (e.g.,whichever detects the interface first), there could be a time delaybefore the pumping of blood components from the chamber 4 isdiscontinued. For example, in a procedure where platelets are beingcollected, at least a slight time delay might maximize a plateletcollection while presenting a relatively low risk of causing asignificant-number of red and white blood cells to be collected alongwith the platelets.

[0145] When the pumping of blood components has been discontinued, thetubing 21 may be clamped shut (via the optional clamp associated withone or more of supports 9-11) and possibly also sealed and cut viasterile welding supplied by one or more of the supports 9-11 (e.g.,support 9). Thereafter, the chamber 4 containing non-desiredconcentrates of particular blood components (e.g., red blood cells,etc.), may be removed from the centrifuge and disposed.

[0146] Systems and methods in accordance with the invention may be usedin the processing of whole blood. For example, FIG. 13 schematicallyillustrates an embodiment of a system configured to process whole blood.As shown in that figure, whole blood from a whole blood source 100(e.g., one/or more donors, and/or one or more containers containingblood donated by one or more donors) may be introduced into a chamber4′, which may be configured at least similar to the chamber 4 discussedabove. For example, the chamber 4′ may include a variable volumeinterior that may be reduced via hydraulic pressure so as to pumpcentrifugally separated blood components from the chamber 4′. Asdiscussed in some of the above examples, alternative pumps may also beused. The pumping may optionally be controlled based on pressure sensingand/or optical sensing in a manner at least similar to that discussedabove in connection with FIGS. 1, 1A, 1B, 5, 7, and 9-12.

[0147] The chamber 4′ may include a single outlet or more than oneoutlet. In the example shown in FIG. 13, separate outlets may beassociated with removal of particular blood components from the chamber4′. In addition, a plurality of collection containers 33′, 33″, and 33′″may be respectively flow coupled to those outlets so as to collectseparate blood components separated in the chamber 4′. For example, thecollection container 33′ may be used to collect a platelet product,collection container 33″ may be used to collect a plasma product, andcollection container 33′″ may be used to collect a red blood cellproduct. One or more of the containers 33′, 33″, and 33′″ may be eitherreceived in centrifuge rotor 1 or positioned at a location outside ofthe centrifugal field.

[0148] One or more of filters 31′, 31″, and 31′″ may be associated witheach of the respective flow paths leading from the chamber 4′ to thecontainers 33′, 33″, and 33′″. The filters 31′, 31″, and 31′″ may beconfigured at least similar to filter 31 discussed above. One or more ofthe filters 31′, 31″. and 31′″ may either be received in a portion ofthe centrifuge rotor 1 or located outside of the centrifugal field.Although FIG. 13 shows a separate, respective filter 31′, 31″, 31′″associated with each of the flow paths leading from the chamber 4′, manyother arrangements are possible. For example, one or more of the filters31′, 31″, and/or 31′″ (e.g., filter 31″) may be omitted, and/or thefilter outlets may be coupled to more than one collection container,and/or a single filter may be used for multiple flow paths.

[0149] In the embodiment of FIG. 13, one or more controllable clampsassociated with one or more the supports 9, 10, 11 may be used tocontrol flow of substances to and/or from the chamber 4′. One or morewelders associated with one or more of the supports 9, 10, and 11 may beused to seal tubing lines leading to the containers 33′, 33″, and 33′″.For example, such clamps and welders may be operated during rotation ofthe rotor 1.

[0150] In some alternative embodiments, other optional components,accessories and/or methods may be used in addition or in lieu of certainfeatures described hereinabove. An example is a leukoreduction system,involving an LRS® chamber described in numerous publications includingvarious U.S. and foreign patents (e.g., U.S. Pat. No. 5,674,173, amongothers). Other potential accessory devices may include sampling devicesof numerous types including, for example, bacteria screening devicesreferred to as Bact-T Alert® devices.

[0151] In addition, an adapted database associated with a barcode readermay be utilized to make all the blood products processed by the systemdirectly traceable and that database may also contain all controlcriteria for feasible blood product processing stages of the system.

[0152] It will be apparent to those skilled in the art that variousmodifications and variations can be made to the structure andmethodology described herein. Thus, it should be understood that theinvention is not limited to the subject matter discussed in thespecification. Rather, the present invention is intended to covermodifications and variations.

What is claimed is:
 1. A system for processing blood components, thesystem comprising: a separation chamber comprising a chamber interior inwhich blood components are centrifugally separated, and an outlet portfor passing at least some of the centrifugally separated bloodcomponents from the chamber interior; a flow path in flow communicationwith the outlet port of the separation chamber; a filter comprising afilter inlet in flow communication with the flow path, a porousfiltration medium configured to filter at least some of at least oneblood component from centrifugally separated blood components passed tothe filter via the flow path, and a filter outlet for filtered bloodcomponents; and a centrifuge rotor configured to be rotated about anaxis of rotation, the rotor comprising a first portion configured toreceive the separation chamber and a second portion configured toreceive the filter, wherein the first and second portions are positionedwith respect to one another so that when the separation chamber isreceived in the first portion and the filter is received in the secondportion, the filter is closer than the interior of the separationchamber to the axis of rotation, wherein the system is configured sothat the rotor rotates during filtering of at least some of said atleast one blood component via the filter.
 2. The system of claim 1,wherein the system is configured so that when the filter is received inthe second portion, the filter is eccentric with respect to the axis ofrotation.
 3. The system of claim 2, wherein the system is configured sothat when the filter is received in the second portion, the filter is atleast close to the axis of rotation and wherein the axis of rotationdoes not intersect an interior flow path defined by the filter.
 4. Thesystem of claim 2, wherein the filter comprises a filter housing inflowport and a filter housing outflow port, and wherein the system isconfigured so that when the filter is received in the second portion,the filter housing outflow port is located closer than the filterhousing inflow port to the axis of rotation.
 5. The system of claim 2,wherein the system is configured so that when the filter is received inthe second portion, the filter housing outflow port is closer than theporous filtration medium to the axis of rotation.
 6. The system of claim2, wherein the system is configured so that when the filter is receivedin the second portion, the filter housing outflow port is above thefilter housing inflow port.
 7. The system of claim 2, wherein the filtercomprises a filter housing defining an interior space containing theporous filtration medium, wherein the filter inlet and filter outlet arein flow communication with the interior space, and wherein the system isconfigured so that when the filter is received in the second portion,the filter is positioned so that blood components flow in the interiorspace in a direction facing generally toward the axis of rotation. 8.The system of claim 7, wherein the filter housing defines a filterhousing inflow port for passing blood components to the interior spaceand a filter housing outflow port for passing blood components from theinterior space, and wherein the system is configured so that when thefilter is received in the second portion, the filter housing outflowport is closer than the filter housing inflow port to the axis ofrotation.
 9. The system of claim 7, wherein the filter housing defines afilter housing inflow port for passing blood components to the interiorspace and a filter housing outflow port for passing blood componentsfrom the interior space, and wherein the system is configured so thatwhen the filter is received in the second portion, the filter housingoutflow port is closer than the porous filtration medium to the axis ofrotation.
 10. The system of claim 7, wherein the filter housing definesa filter housing inflow port for passing blood components to theinterior space and a filter housing outflow port for passing bloodcomponents from the interior space, and wherein the system is configuredso that when the filter is received in the second portion, the filterhousing outflow port is above the filter housing inflow port.
 11. Thesystem of claim 1, wherein the second portion comprises at least one ofa ledge and a slot configured to receive the filter, the at least one ofa ledge and a slot being positioned under a top surface of the rotor.12. The system of claim 1, wherein the rotor comprises a holderconfigured to hold the filter with respect to the rotor.
 13. The systemof claim 1, wherein the flow path comprises a first tubing portionhaving one end coupled to the outlet port of the separation chamber andanother end coupled to the filter inlet, and wherein the system furthercomprises a second tubing portion having an end coupled to the filteroutlet, wherein the second tubing portion extends in a direction facinggenerally away from the axis of rotation.
 14. The system of claim 13,further comprising a third tubing portion downstream from the secondtubing portion, wherein the third tubing portion extends in a directionfacing generally toward the axis of rotation.
 15. The system of claim14, wherein the rotor comprises a groove configured to receive at leastsome of the second and third tubing portions.
 16. The system of claim 1,wherein the system further comprises a collection container comprisingan inlet in flow communication with the filter outlet, and wherein thesecond portion of the rotor comprises a cavity configured to receive thefilter and the collection container.
 17. The system of claim 1, whereinthe axis of rotation extends through the second portion of the rotor.18. The system of claim 1, wherein the chamber is configured so that thechamber interior has a variable volume.
 19. The system of claim 1,wherein the separation chamber comprises a blood component separationbag.
 20. The system of claim 19, wherein at least a portion of the bloodcomponent separation bag is formed of at least one of flexible andsemi-rigid material so that the chamber interior has a variable volume.21. The system of claim 19, wherein the bag has a generally annular ringshape defining a central opening.
 22. The system of claim 19, whereinthe chamber interior includes a tapered portion leading to the outletport.
 23. The system of claim 1, wherein the system comprises a tubingline having an end coupled to the filter outlet, and wherein the rotorcomprises at least one support member configured to support theseparation chamber, wherein the at least one support member comprises aguide groove configured to receive a portion of the tubing line and atleast one of a controllable clamp and a welder associated with thegroove.
 24. The system of claim 23, wherein the separation chambercomprises at least one guide hole configured to receive the at least onesupport member.
 25. The system of claim 1, wherein the rotor comprises aplurality of support members located in an asymmetric fashion withrespect to the axis of rotation, and wherein the separation chambercomprises a plurality of guide holes, each of the guide holes beingconfigured to receive a respective one of the support members.
 26. Thesystem of claim 1, wherein the separation chamber has a ring shape. 27.The system of claim 1, further comprising at least one valving member onthe centrifuge rotor, the valving member being configured to controlflow of at least some of the blood components during rotation of therotor.
 28. The system of claim 27, wherein the valving member comprisesa tubing clamp.
 29. The system of claim 1, further comprising at leastone sealing member on the centrifuge rotor, the sealing member beingconfigured to create a seal during rotation of the rotor.
 30. The systemof claim 29, wherein the sealing member comprises a tubing welder. 31.The system of claim 1, further comprising a pump configured to pump atleast some of the centrifugally separated blood components from thechamber to the filter via the flow path.
 32. The system of claim 31,wherein the system is configured so that the pump pumps blood componentsfrom the chamber during rotation of the centrifuge rotor.
 33. The systemof claim 31, wherein the chamber is configured so that the chamberinterior has a variable volume, and wherein the pump is configured toreduce the volume of the chamber interior.
 34. The system of claim 33,wherein the pump is configured to apply pressure to the chamber viahydraulic fluid.
 35. The system of claim 34, further comprising a sensorconfigured to sense pressure of pumped blood components, wherein thesensor senses pressure of the hydraulic fluid.
 36. The system of claim31, further comprising a sensor configured to sense pressure of pumpedblood components, wherein the system is configured to control the pumpbased on at least the pressure sensed by the pressure sensor.
 37. Thesystem of claim 36, wherein the system is configured to calculate adifference between pressures sensed by the pressure sensor in at leastone time interval, determine when the calculated difference is at leasta predetermined amount, and control the pump in response to at least thedetermination that the calculated difference is at least thepredetermined amount.
 38. The system of claim 36, further comprising anoptical sensor, wherein the system is configured to control the pumpbased on at least information sensed by the optical sensor and pressuresensed by the pressure sensor.
 39. A method of processing bloodcomponents, comprising: providing the system of claim 1; placing theseparation chamber in the first portion of the rotor and the filter inthe second portion of the rotor, wherein the filter is located closerthan an interior of the separation chamber to the axis of rotation ofthe rotor; rotating the centrifuge rotor, the separation chamber, andthe filter about the axis of rotation of the centrifuge rotor, whereinblood components are centrifugally separated in the chamber interior;removing at least some of the centrifugally separated blood componentsfrom the separation chamber via the outlet port; and filtering theremoved blood components with the filter so as to filter at least someof at least one blood component from the removed blood components,wherein at least a portion of the filtering occurs during said rotating.40. A method of processing blood components, comprising: placing aseparation chamber in a first portion of a centrifuge rotor and a filterin a second portion of the rotor, wherein the filter is located closerthan an interior of the separation chamber to an axis of rotation of thecentrifuge rotor, and wherein the filter comprises a porous filtrationmedium; rotating the centrifuge rotor, the separation chamber, and thefilter about the axis of rotation, wherein blood components arecentrifugally separated in a chamber interior of the separation chamber;removing at least some of the centrifugally separated blood componentsfrom the separation chamber via an outlet port of the separationchamber; and filtering the removed blood components with the filter soas to filter at least some of at least one blood component from theremoved blood components, wherein at least a portion of the filteringoccurs during said rotating.
 41. The method of claim 40, wherein themethod further comprises passing the filtered blood components into atleast one collection container.
 42. The method of claim 40, wherein theblood components in the separation chamber are blood components of abuffy coat.
 43. The method of claim 40, wherein whole blood is processedin the method.
 44. The method of claim 40, wherein the filter comprisesa filter housing defining an interior space containing the porousfiltration medium, and wherein the method comprises flowing bloodcomponents in the interior space in a direction facing generally towardthe axis of rotation.
 45. The method of claim 40, further comprisingcausing at least one valving member on the centrifuge rotor to controlflow of at least some of the blood components during rotation of therotor.
 46. The method of claim 45, wherein the valving member comprisesa tubing clamp.
 47. The method of claim 40, further comprising causingat least one sealing member on the centrifuge rotor to create a sealduring rotation of the rotor.
 48. The method of claim 47, wherein thesealing member comprises a tubing welder.
 49. The method of claim 40,further comprising pumping at least some of the centrifugally separatedblood components from the chamber to the filter.
 50. The method of claim49, wherein the pumping occurs during rotation of the centrifuge rotor.51. The method of claim 49, wherein the pumping comprises reducing thevolume of an interior of the chamber.
 52. The method of claim 51,further comprising applying pressure to the chamber via hydraulic fluid.53. The method of claim 49, further comprising sensing pressure ofpumped blood components, and controlling the pumping based on at leastthe sensed pressure.
 54. The method of claim 53, further comprisingcalculating a difference between pressures sensed in at least one timeinterval, determining when the calculated difference is at least apredetermined amount, and controlling the pumping in response to atleast the determination that the calculated difference is at least thepredetermined amount.
 55. The method of claim 53, further comprisingoptically sensing the pumped blood products, and controlling the pumpingbased on at least one of optically sensed information and sensedpressure.
 56. An apparatus for use with a centrifuge for processingblood components, the apparatus comprising: a separation chambercomprising a chamber interior in which blood components arecentrifugally separated, and an outlet port for passing at least some ofthe centrifugally separated blood components from the chamber interior;a flow path in flow communication with the outlet port of the separationchamber; and a filter comprising a filter inlet in flow communicationwith the flow path, a porous filtration medium configured to filter atleast some of at least one blood component from centrifugally separatedblood components passed to the filter via the flow path, and a filteroutlet for filtered blood components, wherein the centrifuge for usewith the apparatus comprises a rotor configured to be rotated about anaxis of rotation, the rotor comprising a first portion configured toreceive the separation chamber and a second portion configured toreceive the filter, wherein the first and second portions are positionedwith respect to one another so that when the separation chamber isreceived in the first portion and the filter is received in the secondportion, the filter is closer than the interior of the separationchamber to the axis of rotation, and wherein the centrifuge isconfigured so that the rotor rotates during filtering of at least someof said at least one blood component via the filter.
 57. The apparatusof claim 56, wherein the apparatus further comprises a collectioncontainer comprising an inlet in flow communication with the filteroutlet, and wherein the second portion of the rotor comprises a cavityconfigured to receive the filter and the collection container.
 58. Thesystem of claim 56, wherein the chamber is configured so that thechamber interior has a variable volume.
 59. The apparatus of claim 56,wherein the separation chamber comprises a blood component separationbag.
 60. The apparatus of claim 59, wherein at least a portion of theblood component separation bag is formed of at least one of flexible andsemi-rigid material so that the chamber interior has a variable volume.61. The apparatus of claim 59, wherein the bag has a generally annularring shape defining a central opening.
 62. The apparatus of claim 59,wherein the chamber interior includes a tapered portion leading to theoutlet port.
 63. The apparatus of claim 56, wherein the separationchamber comprises at least one guide hole configured to receive at leastone support member of the centrifuge.
 64. The apparatus of claim 56,wherein the rotor comprises a plurality of support members located in anasymmetric fashion with respect to the axis of rotation, and wherein theseparation chamber comprises a plurality of guide holes, each of theguide holes being configured to receive a respective one of the supportmembers.
 65. The apparatus of claim 56, wherein the apparatus isconfigured to be disposed after being used for processing of bloodcomponents from a single donor.
 66. The apparatus of claim 56, whereinthe separation chamber has a ring shape.
 67. A system for processingblood components, comprising: a chamber comprising an interiorconfigured to contain separated blood components, and an outlet port forpassing at least some of the separated blood components from theinterior; a flow path in flow communication with the outlet port of thechamber; a filter comprising a filter inlet in flow communication withthe flow path, a porous filtration medium configured to filter at leastsome of at least one blood component from separated blood componentspassed to the filter via the flow path, and a filter outlet for filteredblood components; a pump configured to pump at least some of theseparated blood components from the chamber to the filter via the flowpath; and a pressure sensor configured to sense pressure of bloodcomponents pumped to the filter, wherein the system is configured tocontrol the pump based on at least the pressure sensed by the pressuresensor.
 68. The system of claim 67, wherein the pump comprises a portionof a centrifuge.
 69. The system of claim 67, wherein the pump comprisesat least a portion of a blood component expresser.
 70. The system ofclaim 67, wherein the chamber comprises a separation chamber, whereinblood components are centrifugally separated in the interior of thecontainer, and wherein the system further comprises a centrifuge rotorconfigured to be rotated about an axis of rotation, the rotor comprisinga portion configured to receive the chamber.
 71. The system of claim 70,wherein the system is configured so that the pump pumps blood componentsfrom the chamber during rotation of the centrifuge rotor.
 72. The systemof claim 70, further comprising at least one valving member on thecentrifuge rotor, the valving member being configured to control flow ofat least some of the blood components during rotation of the rotor. 73.The system of claim 72, wherein the valving member comprises a tubingclamp.
 74. The system of claim 70, further comprising at least onesealing member on the centrifuge rotor, the sealing member beingconfigured to create a seal during rotation of the rotor.
 75. The systemof claim 74, wherein the sealing member comprises a tubing welder. 76.The system of claim 70, wherein the rotor further comprises a portionconfigured to receive the filter, and wherein the system is configuredso that the rotor rotates during filtering via the filter.
 77. Thesystem of claim 76, wherein the filter comprises a filter housingdefining an interior space containing the porous filtration medium,wherein the system is configured so that when the filter is received inthe portion of the rotor configured to receive the filter, the filter ispositioned so that blood components flow in the interior space in adirection facing generally toward the axis of rotation.
 78. The systemof claim 67, wherein the chamber comprises a bag formed of at least oneof flexible and semi-rigid material so that the interior of the chamberhas a variable volume.
 79. The system of claim 78, wherein the bag has agenerally annular shape defining a central opening.
 80. The system ofclaim 67, wherein the chamber is configured so that the interior of thechamber has a variable volume.
 81. The system of claim 80, wherein thepump is configured to reduce the volume of the chamber interior.
 82. Thesystem of claim 81, wherein the pump is configured to apply pressure tothe chamber via hydraulic fluid.
 83. The system of claim 82, wherein thesensor senses pressure of the hydraulic fluid.
 84. The system of claim67, wherein the system is configured to calculated a difference betweenpressures sensed by the pressure sensor in at least one time intervalwhere blood components are pumped by the pump, determine when thecalculated difference is at least a predetermined amount, and controlthe pump in response to at least the determination that the calculateddifference is at least the predetermined amount.
 85. The system of claim67, further comprising an optical sensor, wherein the system isconfigured to control the pump based on at least information sensed bythe optical sensor and pressure sensed by the pressure sensor.
 86. Thesystem of claim 85, wherein said optical sensor is positioned to senseblood components in the chamber.
 87. The system of claim 85, whereinsaid optical sensor is positioned to sense blood components in a tubingline in flow communication with the filter.
 88. The system of claim 85,wherein said optical sensor comprises a first optical sensor and asecond optical sensor, the first optical sensor being positioned tosense blood components in the chamber and the second optical sensorbeing positioned to sense blood components in a tubing line in flowcommunication with the filter.
 89. A method of processing bloodcomponents, comprising: providing the system of claim 67; pumping, viathe pump, at least some of the separated blood components from thechamber; filtering the pumped blood components with the filter so as tofilter at least some of at least one blood component from the pumpedblood components; sensing, via the pressure sensor, pressure of bloodcomponents pumped to the filter; and controlling the pumping based on atleast the pressure sensed by the pressure sensor.
 90. A method ofprocessing blood components, comprising: pumping at least some separatedblood components from a chamber; filtering the pumped blood componentswith a filter so as to filter at least some of at least one bloodcomponent from the pumped blood components, wherein the filter comprisesa porous filtration membrane; sensing pressure of blood componentspumped to the filter; and controlling the pumping based on at least thepressure sensed by the pressure sensor.
 91. The method of claim 90,further comprising rotating the chamber about an axis of rotation,wherein blood components are centrifugally separated in an interior ofthe chamber.
 92. The method of claim 91, wherein the pumping occursduring rotation of the chamber.
 93. The method of claim 91, wherein acentrifuge is used to rotate the chamber, and wherein said at least someseparated blood components are pumped from the chamber while the chamberis received on a rotor of the centrifuge.
 94. The method of claim 93,further comprising causing at least one valving member on the centrifugerotor to control flow of at least some of the blood components duringrotation of the rotor.
 95. The method of claim 94, wherein the valvingmember comprises a tubing clamp.
 96. The method of claim 93, furthercomprising causing at least one sealing member on the centrifuge rotorto create a seal during rotation of the rotor.
 97. The method of claim96, wherein the sealing member comprises a tubing welder.
 98. The methodof claim 91, wherein a centrifuge is used to rotate the chamber, andwherein said at least some separated blood components are pumped fromthe chamber after the chamber is removed from a rotor of the centrifuge.99. The method of claim 90, further comprising rotating the filter aboutan axis of rotation during the filtering.
 100. The method of claim 99,wherein the filter comprises a filter housing defining an interior spacecontaining the porous filtration medium, and wherein the methodcomprises flowing blood components in the interior space in a directionfacing generally toward the axis of rotation.
 101. The method of claim90, wherein the chamber is configured so that an interior of the chamberhas a variable volume, and wherein the pumping comprises reducing thevolume of the interior of the chamber.
 102. The method of claim 101,further comprising applying pressure to the chamber via hydraulic fluid.103. The method of claim 90, further comprising calculating a differencebetween pressures sensed in at least one time interval, determining whenthe calculated difference is at least a predetermined amount, andcontrolling the pumping in response to at least the determination thatthe calculated difference is at least the predetermined amount.
 104. Themethod of claim 90, further comprising optically sensing the pumpedblood products, and controlling the pumping based on at least one ofoptically sensed information and sensed pressure.
 105. The method ofclaim 104, wherein optically sensing comprises optically sensing bloodcomponents in the chamber.
 106. The method of claim 104, whereinoptically sensing comprises optically sensing blood components in atubing line in flow communication with the filter.
 107. The method ofclaim 104, wherein optically sensing comprises optically sensing bloodcomponents in the chamber and optically sensing blood components in atubing line in flow communication with the filter.
 108. The method ofclaim 90, wherein the method further comprises passing the filteredblood components into at least one collection container.
 109. The methodof claim 90, wherein the blood components in the chamber are bloodcomponents of a buffy coat.
 110. The method of claim 90, wherein wholeblood is processed in the method.
 111. A system for processing bloodcomponents, comprising: a separation chamber comprising a chamberinterior in which blood components are centrifugally separated, and anoutlet port for passing at least some of the centrifugally separatedblood components from the chamber interior; a flow path in flowcommunication with the outlet port of the separation chamber; a pumpconfigured to pump at least some of the centrifugally separated bloodcomponents from the chamber and through the flow path; and a pressuresensor configured to sense pressure of blood components pumped by thepump; and a centrifuge rotor configured to be rotated about an axis ofrotation, the rotor comprising a portion configured to receive theseparation chamber, wherein the system is configured to calculate adifference between pressures sensed by the pressure sensor in at leastone time interval, determine when the calculated difference is at leasta predetermined amount, and control the pump in response to at least thedetermination that the calculated difference is at least thepredetermined amount.
 112. The system of claim 111, wherein the systemis configured so that the pump pumps blood components from the chamberduring rotation of the centrifuge rotor.
 113. The system of claim 111,further comprising at least one valving member on the centrifuge rotor,the valving member being configured to control flow of at least some ofthe blood components during rotation of the rotor.
 114. The system ofclaim 113, wherein the valving member comprises a tubing clamp.
 115. Thesystem of claim 111, further comprising a sealing member on thecentrifuge rotor, the sealing member being configured to create a sealduring rotation of the rotor.
 116. The system of claim 115, wherein thesealing member comprises a tubing welder.
 117. The system of claim 111,further comprising a filter comprising a porous filtration membraneconfigured to filter at least one blood component from the pumped bloodproducts.
 118. The system of claim 111, wherein the chamber comprises abag formed of at least one of flexible and semi-rigid material so thatthe interior of the chamber has a variable volume.
 119. The system ofclaim 118, wherein the bag has a generally annular shape defining acentral opening.
 120. The system of claim 111, wherein the chamber isconfigured so that the chamber interior has a variable volume,
 121. Thesystem of claim 120, wherein the pump is configured to reduce the volumeof the chamber interior.
 122. The system of claim 121, wherein the pumpis configured to apply pressure to the chamber via hydraulic fluid. 123.The system of claim 122, wherein the sensor senses pressure of thehydraulic fluid.
 124. The system of claim 111, further comprising anoptical sensor, wherein the system is configured to control the pumpbased on at least information sensed by the optical sensor and pressuresensed by the pressure sensor.
 125. The system of claim 124, whereinsaid optical sensor is positioned to sense blood components in thechamber.
 126. The system of claim 124, wherein said optical sensor ispositioned to sense blood components in a tubing line in flowcommunication with the filter.
 127. The system of claim 124, whereinsaid optical sensor comprises a first optical sensor and a secondoptical sensor, the first optical sensor being positioned to sense bloodcomponents in the chamber and the second optical sensor being positionedto sense blood components in a tubing line associated with the flowpath.
 128. A method of processing blood components, comprising:providing the system of claim 111; rotating the centrifuge rotor and thechamber about the axis of rotation, wherein blood components arecentrifugally separated in the chamber; pumping, via the pump, at leastsome separated blood components from the chamber; sensing, via thepressure sensor, pressure of pumped blood components; calculating adifference between pressures sensed in at least one time interval;determining when the calculated difference is at least a predeterminedamount; and controlling the pumping in response to at least thedetermination that the calculated difference is at least thepredetermined amount.
 129. A method of processing blood components,comprising: rotating a chamber about an axis of rotation, wherein bloodcomponents are centrifugally separated in the chamber; pumping at leastsome separated blood components from the chamber; sensing pressure ofpumped blood components; calculating a difference between pressuressensed in at least one time interval; determining when the calculateddifference is at least a predetermined amount; and controlling thepumping in response to at least the determination that the calculateddifference is at least the predetermined amount.
 130. The method ofclaim 129, wherein the pumping occurs during rotation of the chamber.131. The method of claim 129, wherein the chamber is rotated via acentrifuge rotor, and wherein the method further comprises causing atleast one valving member on the centrifuge rotor to control flow of atleast some of the blood components during rotation of the rotor. 132.The method of claim 131, wherein the valving member comprises a tubingclamp.
 133. The method of claim 129, wherein the chamber is rotated viaa centrifuge rotor, and wherein the method further comprises causing atleast one sealing member on the centrifuge rotor to create a seal duringrotation of the rotor.
 134. The method of claim 133, wherein the sealingmember comprises a tubing welder.
 135. The method of claim 129, furthercomprising filtering the pumped blood components with a filter so as tofilter at least some of at least one blood component from the pumpedblood components, wherein the filter comprises a porous filtrationmembrane.
 136. The method of claim 135, wherein the rotating furthercomprises rotating the filter about the axis of rotation.
 137. Themethod of claim 136, wherein the filter comprises a filter housingdefining an interior space containing the porous filtration medium, andwherein the method comprises flowing blood components in the interiorspace in a direction facing generally toward the axis of rotation. 138.The method of claim 129, wherein the chamber is configured so that aninterior of the chamber has a variable volume, and wherein the pumpingcomprises reducing the volume of the interior of the chamber.
 139. Themethod of claim 138, further comprising applying pressure to the chambervia hydraulic fluid.
 140. The method of claim 129, further comprisingoptically sensing the pumped blood products, and controlling the pumpbased on at least one of optically sensed information and sensedpressure.
 141. The method of claim 140, wherein optically sensingcomprises optically sensing blood components in the chamber.
 142. Themethod of claim 140, wherein optically sensing comprises opticallysensing blood components in a tubing line in flow communication with thefilter.
 143. The method of claim 140, wherein optically sensingcomprises optically sensing blood components in the chamber andoptically sensing blood components in a tubing line.
 144. The method ofclaim 129, wherein the method further comprises passing at least some ofthe pumped blood components into at least one collection container. 145.The method of claim 129, wherein the blood components in the chamber areblood components of a buffy coat.
 146. The method of claim 129, whereinwhole blood is processed in the method.
 147. A method of determining alocation of at least one interface during processing of bloodcomponents, comprising: pumping at least some centrifugally separatedblood components from a chamber; sensing pressure of the pumped bloodcomponents; and determining a location of at least one interface basedon the sensed pressure, wherein the interface is associated with thepumped blood components.
 148. The method of claim 147, wherein theinterface comprises at least one of an interface between bloodcomponents and air, and an interface between differing blood components.149. The method of claim 147, further comprising rotating a chamberabout an axis of rotation, wherein blood components are centrifugallyseparated in the chamber.
 150. The method of claim 149, wherein thepumping occurs during rotation of the chamber.
 151. The method of claim149, wherein the chamber is rotated via a centrifuge rotor, and whereinthe method further comprises causing at least one valving member on thecentrifuge rotor to control flow of at least some of the bloodcomponents during rotation of the rotor.
 152. The method of claim 151,wherein the valving member comprises a tubing clamp.
 153. The method ofclaim 149, wherein the chamber is rotated via a centrifuge rotor, andwherein the method further comprises causing at least one sealing memberon the centrifuge rotor to create a seal during rotation of the rotor.154. The method of claim 153, wherein the sealing member comprises atubing welder.
 155. The method of claim 149, further comprisingfiltering pumped blood components with a filter so as to filter at leastsome of at least one blood component from the pumped blood components,wherein the filter comprises a porous filtration membrane.
 156. Themethod of claim 155, wherein the rotating further comprises rotating thefilter about the axis of rotation.
 157. The method of claim 156, whereinthe filter comprises a filter housing defining an interior spacecontaining the porous filtration medium, and wherein the methodcomprises flowing blood components in the interior space in a directionfacing generally toward the axis of rotation.
 158. The method of claim147, further comprising filtering pumped blood components with a filterso as to filter at least some of at least one blood component from thepumped blood components, wherein the filter comprises a porousfiltration membrane.
 159. The method of claim 147, wherein the chamberis configured so that an interior of the chamber has a variable volume,and wherein the pumping comprises reducing the volume of the interior ofthe chamber.
 160. The method of claim 159, further comprising applyingpressure to the chamber via hydraulic fluid.
 161. The method of claim147, further comprising optically sensing the pumped blood products, andwherein the location of the location of the at least one interface isbased on the sensed pressure and optically sensed information.
 162. Themethod of claim 147, wherein the blood components in the chamber areblood components of a buffy coat.
 163. The method of claim 147, whereinwhole blood is processed in the method.